1. Field of the Invention
This invention relates to a homogeneous, concentrated water-containing liquid detergent and to its use for the manual and machine washing of fabrics.
2. Statement of Related Art
Liquid water-containing laundry detergents containing anionic and nonionic surfactants are well known, European patent application EP 367 049 (BASF) describes liquid detergents containing anionic and nonionic surfactants and a special partly esterified copolymer. These liquid detergents consist of clear, aqueous, generally alkaline solutions which are stable in storage and which have an improved primary and secondary washing effect compared with state-of-the-art detergents. The concentrated water-containing liquid detergents described in this document contain 10 to 30% by weight typical anionic surfactants and 5 to 20% By weight nonionic surfactants and 0.1 to 20% by weight partly esterified copolymer.
Water-containing liquid detergents which contain a mixture of anionic and nonionic surfactants and in which the content of nonionic surfactants, based on the liquid detergent as a whole, is more than 20% by weight generally have inhomogeneities which cause phase separation of the liquid detergent, for example separation into two clear liquid phases or the flocculation of a solid. This phase separation occurs either directly during production, during storage for several weeks (instability in storage) or on dilution with water.
It has now been found that concentrated aqueous liquid detergents having a nonionic surfactant content above 20% by weight do not have the disadvantages mentioned above providing they contain a certain surface-active sulfonate.